Should be a fairly good match. I'd also pop for a SSD too but you will want to keep you expectations in check. Finally, a pair of 4GB RAM sticks so you maximize what you have.
I have a Dell Optiplex 780. I am looking for good inexpensive parts that can run games such as Rust, Civ 6, etc. My processor is an Intel Core 2 Duo CPU E8400. Thank you!